Retrospective Planning Permission in London: What to Do If Works Were Done Without Consent

Built-without-consent situations are common in London residential properties -- particularly in the large stock of Victorian and Edwardian terrace housing where extensions, loft conversions, and internal alterations have been carried out over many decades, sometimes without the planning permission or building regulations approval that would have been required at the time.

The issue typically comes to light when the property is being sold, remortgaged, or when an owner decides to carry out further work and a building surveyor or solicitor identifies the lack of consents. This guide explains the options for resolving built-without-consent situations in London.

The first question in any built-without-consent situation is whether the local planning authority (LPA) can still take enforcement action. Under the Town and Country Planning Act 1990:

For operational development (building works): the enforcement time limit is 4 years from the date the operations were substantially complete. After 4 years, the LPA cannot issue an enforcement notice for the works.

For material change of use: the enforcement time limit is 10 years from the date of the change of use.

For breach of condition: the enforcement time limit is 10 years from the date of the breach.

Listed building offences: there is NO time limit for listed building enforcement. A breach of listed building consent requirements can be enforced at any time.

Once the enforcement time limit has passed, the development is immune from enforcement. However, this does not mean the works are necessarily lawful in planning terms -- it means enforcement action cannot be taken.

Where works have been carried out without planning permission and the 4-year (or 10-year) time limit has passed, the owner can apply for a Certificate of Lawful Existing Use or Development (CLEUD) from the local planning authority. The CLEUD confirms that the works are immune from enforcement action.

Evidence required for a CLEUD application:

• Statutory declarations from the owner and, where possible, previous owners, neighbours, or others with direct knowledge confirming the date the works were completed and the continuous use since
• Planning application history, land registry entries, photographs, utility bills, and other documentary evidence
• Electoral roll records or council tax records that show continuous residential occupation

A CLEUD is a significant legal document that resolves the planning status of the works and satisfies solicitors in a property sale. It is typically a better solution than indemnity insurance for significant or high-value works.

Timeframe and cost: a CLEUD application takes 8 weeks to determine. Professional fees for preparation of the application typically range from £1,000--£2,500.

Where the 4-year time limit has not passed (the works were done more recently), the owner can apply for retrospective planning permission. Applying retrospectively does not guarantee approval -- the application is assessed on the same planning merits as any new application. If refused, the LPA can issue an enforcement notice requiring demolition of the works.

Retrospective planning applications should be approached carefully. Submitting a retrospective application draws the LPA's attention to the works. If the works clearly comply with planning policy, retrospective consent is likely. If the works would not have been approved, the retrospective application may trigger enforcement action that would not otherwise have occurred.

Before submitting retrospectively: take planning advice from a consultant to assess the prospects of approval.

Planning consent and Building Regulations approval are entirely separate systems. Works done without Building Regulations approval are a different category of non-compliance from works done without planning permission.

Building Regulations enforcement: there is no statutory time limit for Building Regulations enforcement notices. However, Building Control typically does not proactively seek out historic non-compliance. Issues arise when the property is sold and a surveyor or buyer identifies the absence of a completion certificate.

Regularisation certificate: for works completed without Building Regulations approval, the local authority building control body can issue a Regularisation Certificate following an inspection of the existing works. The inspection may require opening up of finishes to check the structural and insulation elements. This is the correct route where the works can be inspected and found to comply.

Indemnity insurance: where a Regularisation Certificate is not practical (e.g., the works are not accessible, or the cost of opening up is prohibitive), structural warranties and Building Regulations indemnity insurance can be used in property transactions. Indemnity insurance is available from specialist underwriters and is typically a one-off premium. It is acceptable to most mortgage lenders for standard residential transactions.

Built-without-consent issues are most frequently identified and resolved in the context of a property sale:

1. The seller's solicitor prepares a property information form that asks whether works have been carried out and whether planning and building regulations consents were obtained.
2. If gaps are identified, the buyer's solicitor will typically require resolution before exchange of contracts.
3. Resolution options: CLEUD application (for time-expired planning breaches), retrospective planning application, Regularisation Certificate, or indemnity insurance.

The appropriate solution depends on the nature, age, and extent of the works, and on the preferences of the buyer's solicitor and mortgage lender.

rcbGroup advises clients on the consent status of proposed works and existing structures as part of our pre-construction review. Where we identify potential consent gaps for existing works on a property, we guide clients to the appropriate planning consultant or solicitor for resolution.

Contact our team to discuss the consent position for your London property.